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Freshwater fish species and Baltic salmon (Salmo salar) are important to small-scale fisheries in Finland and Sweden. The formerly local markets for these species have expanded as trade has been opened up to international competition. In this study we use cointegration analysis to test the spatial integration of freshwater fish markets in Finland and between Finland and Sweden. The analysed fish species are salmon, perch (Perca fluviatilis), pikeperch (Sander lucioperca), European whitefish (Goregonus lavaretus) and pike (Exos lucius), and the data covers ex-vessel prices from 1993 or 1995 to 2004. We found that the regional prices in Finland were cointegrated. This indicates that the prices are determined on a single market in Finland. Moreover, the study suggests that Finnish and Swedish markets in Baltic salmon, whitefish, pikeperch and perch were partially integrated, while integration of pike markets could not be found. The political implication is that an essential part of the local small-scale fisheries’ operational environment is determined outside the national borders.  相似文献   
2.
Regional socio-economic importance of fisheries in Finland   总被引:1,自引:0,他引:1  
The total value of Finnish fisheries production in 1997 was almost FIM 2 billion. The bulk of this sum was from processing and wholesaling, but in terms of value added, somewhat more than half was contributed by the primary sector, i.e. fishing and fish farming. In economic terms, fisheries accounted for 0.1% of gross domestic product (GDP) in 1997 and the relative job creation capacity was 0.15%. This paper examines the structure of Finnish fisheries in terms of production value and employment. It also considers the level of dependency on fisheries and of value added along the production chain. The focus is on concentration of the industry and on input to the economy at the regional level. The concentration of fisheries and regional dependence on fisheries are assessed in absolute and relative terms. Examining employment and value added in these two ways enables the regional nature of fisheries to be shown in greater detail. The input of fisheries to the regional economy is examined by the share of value added and by location quotients. The location quotient compares an area's share of a particular activity with that area's share of some basic or aggregated phenomenon. The location quotient showed that fisheries have importance not only in the coastal area but also inland.  相似文献   
3.
In addition to its well-known physicochemical properties, hyaluronate (HA) has recently been shown to have important biological and pathophysiologic regulatory effects on granulocytes, monocytes, fibroblasts, and endothelial cells, as well as on the healing of wounds and various joint disorders. Many of these effects depend on or are reflected in the concentration and degree of polymerization of HA. Therefore, high-performance liquid chromatography with size-exclusion column was used to characterize the concentration and degree of polymerization of HA in equine synovial fluid (SF). The mean (+/- SD) HA concentration was 0.47 +/- 0.19 mg/ml and there was no difference between control joints and those with positive response to local anesthetic administration (0.61 +/- 0.20 mg/ml vs 0.42 +/- 0.17 mg/ml), suggesting that in horses with acute traumatic synovitis causing lameness, HA concentration in SF cannot be used as a marker for the condition. High-performance liquid chromatograms disclosed considerable variation between horses in the degree of polymerization reflected in the peak area to height ratio (mean +/- SD, 3.207 +/- 0.447; range, 2.229 to 3.915), indicating differences in local synthesis, degradation, or mobilization into lymph of SF HA. In addition, the correlation between SF HA concentration and degree of polymerization was 0.760 (P less than 0.01; linear regression analysis), suggesting that HA concentration and chain length are independently regulated.  相似文献   
4.
Electrofishing techniques are widely used for the estimation of the size of stream‐dwelling fish populations for both fishery management and scientific study. In contrast to multiple pass, population depletion methods, single‐pass catch‐per‐unit‐effort (CPUE) methods are less time‐consuming and labour‐intensive. A possible issue with the commonly used fixed total time CPUE protocol is that it does not differentiate between the time spent actively fishing and the time incurred while not actively fishing (e.g. removing fish from nets and navigating the site). This issue is likely related to fish density. This study compared two methods of CPUE electrofishing and tested the hypothesis that time spent handling fish and navigating a site can be a source of error in the commonly used fixed total time electrofishing method. Seventy‐one sites were sampled across three subcatchments in the Foyle catchment in Northern Ireland. We found a difference in the catch per unit time between the two methods and that this difference increased with fish density. The fixed‐time CPUE method also failed to detect a species presence in low‐density sites.  相似文献   
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There is generally a very poor understanding of how anadromous brown trout, Salmo trutta, use marine ecosystems. In this study, we use acoustic telemetry techniques to test four alternative hypotheses for estuarine coastal habitat use by this species on a population in the Clyde, west-central Scotland. Anadromous brown trout in their second (or more) summer feeding in the marine environment did not show patterns of estuarine use predicted from studies on other populations of this species. They did not (a) use the inner Clyde Estuary as a staging post for onward migration to open coastal waters, nor did they (b) pass through the estuary rapidly nor did they (c) make multiple incursions into freshwater. In contrast, fish utilised a very geographically constrained area of the inner estuary (<8 km in length), within which fish were highly mobile, exhibiting more activity during a flooding tide and exhibited high survivorship compared with reports from other studies. The reasons why estuarine use by anadromous brown trout in the Clyde may differ from that reported elsewhere is discussed.  相似文献   
7.
Abstract

In this case study, we describe the evolution of Finnish salmon trout aquaculture; how salmon trout farming grew as a vital industry, how Finland became the world's leading producer of salmon trout, and how the opening of markets to international competition led to a decline of the industry. The focus is on the continuous interaction between the changing market situation and production decisions. The study reveals the impact of national environmental policy on the competitiveness of the industry. At the moment, the industry is undergoing major structural changes; production has moved to neighbouring countries, and the value chain is concentrated. In future, closer interaction and co‐operation between the actors along the entire fish value chain will be the key factors for success.  相似文献   
8.
Atlantic salmon populations appear to fluctuate stochastically through time. It is suspected that both density‐dependent and density‐independent factors cause these fluctuations but the relative importance of each, and the life stages at which they operate, is not well known. In this study, a long‐term data set on Atlantic salmon migrants returning to the Foyle catchment, Ireland, was used to determine the role of density‐dependent and life stage‐specific environmental factors regulating population size. A Ricker density‐dependent model showed that spawning adult population size significantly predicted variation in the resultant filial generation; however, a large amount of variation (ca. 68%) remained unexplained. It was shown that environmental factors were significant in explaining some of the remaining variance and that these influences were linked to specific life stages. Three life stages—spawning and incubation, fry emergence and marine survival—were shown to have significant environmental effects that resulted in changes in the returning cohort strength. It is concluded that these life stage‐specific environmental effects are likely to contribute to the stochastic variation in population size resulting from the application of traditional stock–recruitment models. The identification and quantification of these effects should allow improved model accuracy.  相似文献   
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